As I wrote in You Never Give Me Your Money, "In May 1979, Starkey, McCartney and Harrison made music for the first time since January 1970 - drunken, shambolic music, but together nonetheless. The occasion was the wedding celebration for Eric Clapton and Pattie Boyd. Clapton recalled, 'John later phoned me to say that he would have been there too if he had known about it', but no one thought to invite him."
That much is indisputable, although I remain doubtful whether Lennon would have turned up even if he had been invited. What's never likely to be known, however, given the degree of intoxication experienced by all the participants in this wedding-party jam session, is what material the three Beatles (and their equally inebriated buddies) performed.
In the book, I report that the ensemble "stumbled through such familiar material as 'Get Back', 'Sgt. Pepper' and 'Lawdy Miss Clawdy'." But in the interests of accuracy, I ought to add here that some witnesses claimed that no Beatles material was attempted or destroyed on this occasion, the repertoire being dominated by Lonnie Donegan's skiffle material. Given the size of Donegan's ego, and the ex-Beatles' collective devotion to his 50s hits, I think it's pretty safe to say that once the skiffle king took centre-stage for such numbers as 'Cumberland Gap' and 'Pick A Bale Of Cotton', he'd have been unlikely to let any youngsters like McCartney and Harrison anywhere near a microphone. Still wish I'd been there, though.